<template>
    <el-breadcrumb class="app-breadcrumb" separator="/">
        <transition-group name="breadcrumb">
            <el-breadcrumb-item
                v-for="(item, index) in levelList"
                :key="item.path"
            >
                <span
                    v-if="item.redirect === 'noRedirect' ||index == levelList.length - 1"
                    class="no-redirect">{{ item.meta.title }}
                </span>
                <a v-else @click.prevent="handleLink(item)" class="no-redirect">
                    {{item.meta.title}}
                </a>
            </el-breadcrumb-item>
        </transition-group>
    </el-breadcrumb>
</template>

<script>
export default {
    data() {
        return {
            levelList: null
        }
    },
    watch: {
        $route(route) {
            // if you go to the redirect page, do not update the breadcrumbs
            if (route.path.startsWith('/redirect/')) {
                return
            }
            this.getBreadcrumb()
        }
    },
    created() {
        this.getBreadcrumb()
    },
    methods: {
        getBreadcrumb() {
            // only show routes with meta.title
            let matched = this.$route.matched.filter(
                (item) => item.meta && item.meta.title
            )
            const first = matched[0]

            if (!this.isDashboard(first)) {
                matched = [{ path: '/exception/statistics/', meta: { title: '首页' } }].concat(
                    matched
                )
            }

            this.levelList = matched.filter(
                (item) =>
                    item.meta &&
                    item.meta.title &&
                    item.meta.breadcrumb !== false
            )
        },
        isDashboard(route) {
            const name = route && route.name
            if (!name) {
                return false
            }
            return name.trim() === 'Index'
        },
        handleLink(item) {
            const { redirect, path } = item
            if (redirect) {
                this.$router.push(redirect)
                return
            }
            this.$router.push(path)
        }
    }
}
</script>

<style lang="scss" scoped>
.app-breadcrumb.el-breadcrumb {
    display: inline-block;
    font-size: 14px;
    line-height: 50px;
    margin-left: 8px;

    .no-redirect {
        color: #fff;
        cursor: text;
    }
}
</style>
